And I'm Steve Inskeep. The Supreme Court says Michigan voters were within their rights. The court upheld Michigan's ban on using race as a factor in public college admissions. We've called Lee Bollinger, president of Columbia University, who has a personal connection to this issue. As the former president of the University of Michigan, he was the defendant in two landmark affirmative action cases. Welcome to the program, sir.

LEE BOLLINGER: Thank you very much.

INSKEEP: How significant a ruling is this?

BOLLINGER: Well, it's very significant because it - it says essentially that states can, if they choose, to amend their constitutions or change their fundamental law to forbid universities in the state from taking account of race in admissions from affirmative action policies. There are now about 10 states that do that, and this has been a route that the people who are opposed to affirmative action have followed. So this opens the door for more of that.

INSKEEP: Although, of course, supporters of this would point out that it doesn't actually ban affirmative action, it merely says, as some of the justices wrote, that it allows the people to decide whether affirmative action should continue.

BOLLINGER: The issue is, then, this is a new sort of battleground for thinking about issues of race in America. And it will be significant because in each of the states where this kind of amendment has been made to the state constitution or fundamental law, there's been a severe drop in the number of African-American, Hispanic, and Native American students in their public universities.

INSKEEP: And that includes the state of Michigan. I'm looking at a chart here that says that black enrollment at University of Michigan, actually, was up near 10 percent and has now gone down to five percent of freshmen being black in 2011. You believe that's because of the change in affirmative action laws in Michigan?

BOLLINGER: Yes. I mean that's a given.

INSKEEP: And is that a nationwide trend then, you're saying?

BOLLINGER: Well, it's a nationwide trend in the sense that if you don't have affirmative action policies, which have been in effect all across the country for universities and colleges since the 1970s, if you don't have those, then you have a very small number of African-American, Hispanic, Native American students. And that's been viewed as one of the great successes of American society since Brown versus Board of Education in 1954, 60 years ago. So it's a loss to not have this.

INSKEEP: Is there an alternative? There are, of course, some places that attempt to measure, for example, socioeconomic background, to go for low income students rather than trying to measure too specifically on race.

BOLLINGER: Yes. I mean, this is - often race is a way to get racial and ethnic diversity without having to take it into account. And there's a very simple answer to this, which is all universities want low income students and to make sure there's opportunity for access to higher education, but we also want racial and ethnic diversity. And the only way to get that is by actually considering it in the way we do geography and international and legacies and so on.

And the reason is that the population in every segment of the American income stream is largely white, just by virtue of the numbers. And so if you know nothing about an applicant other than they come from low income families, you're more likely to be admitting another white student.

INSKEEP: As a university president and as someone who obviously disagreed with this decision, what do you see as your way forward and the university community's way forward?

BOLLINGER: Well, I think the universities really have to take the lead here because this has been something that, really, as I said, since Brown versus Board of Education and the effort to really desegregate and integrate American society, universities have tried to play their part. We talk today much more in terms of educational advantages, benefits of diversity, and that's important, but we're actually fairly thin in how we explain it.

And I think one of the things we have to do is to take account of the reality of the legacy of racial discrimination in the country and the fact that many of our schools are re-segregated. There's a recent report in which you've been part of that speaks about the re-segregation of the American South - half of the black students attend all-black schools.

New York State is one of the most segregated states in the country in terms of blacks attending largely all-black schools - about 64 percent...